Image by Gerd Altmann from Pixabay, CCO

One of the things that distinguish the United States from almost every other country is also one of the most basic. We write the date differently.

In the U.S., the date is written mm/dd/yyyy, or sometimes mm/dd/yy. For most of the world, this is backward (or, more accurately, sideways.) Why we do this has been much discussed and debated over time and there is no clearly accepted reason. In fact, it defies logic.

It’s called, and I’m not making this up, middle-endianness. The term comes from computer science, in which bytes are arranged according to size. If they are ordered from smallest to largest, the order is called small-endian. The most common method of writing a date is this method: dd/mm/yyyy. Likewise, the largest to smallest organization is big-endian. This method of writing the date is used in China and in most computer applications. But, somehow, here in America, we chose the middle size to come first.

To add to the confusion, we pronounce the date differently from the way we write it!

The day is typically spoken as an ordinal number. An ordinal number is the chronological or sequential position of order. First is followed by second, which is followed by third, and so on. The year is spoken of as a cardinal number. A cardinal number is a quantity of something, such as six or twenty. It can also be a compound number, such as two hundred twenty-six.

So, in the U.S., the twentieth day of September in the year 2020 would be numerically written as 9/20/20. We would write the date as September 20, 2020. But we would say the date as September twentieth, twenty-twenty.

Years should be written as numerals, except at the beginning of a sentence.

• I was born in 1978.
• Nineteen seventy-eight was the year of the great Northeast blizzard. Nine months later, I was born.

In the month/day/year format, remember to place commas after the day and year.

• I was born on November 7, 1978, in an old mill town in Vermont.

If you are writing a date incorporating a day of the week, use a comma after the day of the week.

• I was born on Monday, November the seventh, 1978.
• I was born on Monday, November 7^th, 1978.

The problem with all this is the sheer lack of a good reason for any of it. This is, quite simply, just the way Americans have done it and will continue to do it. But, now that you know the rules, you can do it too.